离子液体法制备再生细菌纤维素纤维

Preparation of regenerated bacterial cellulose nascent fibers prepared by ionic liquid process

以离子液体(氯化1-甲基-3-正丁基咪唑)溶解高聚合度细菌纤维素(BC),采用湿法纺丝制备再生细菌纤维素(RBC)初生纤维;通过红外光谱分析(FTIR)、广角X射线衍射(WAXD)分析、热失重(TG)分析、扫描电镜(SEM)、单丝强度拉伸等表征了RBC初生纤维的结构和性能。结果表明:该溶剂体系通过10 h的快速搅拌溶解即可完全溶解BC,其溶解过程以物理变化为主,无衍生物生成;RBC初生纤维的晶型由纤维素Ⅰ型转变为纤维素Ⅱ型,结晶度明显下降,其断裂强度为0.54～1.36 cN/dtex,并随着凝固浴温度的降低而增强,在凝固浴中加入适量的无水乙醇有利于纤维强度的提高;RBC初生纤维的热稳定性相对于BC略有下降;RBC初生纤维表面粗糙、沟槽纵横,且初生纤维的皮层较薄,其芯层结构较为致密,存在少量微孔。

Bacterial cellulose （BC） with high polymerization degree was dissolved in the ionic liquid of 1-N-butyl-3-methylimi- dazolium chloride and was spun into regenerated bacterial cellulose （RBC） nascent fiber by wet spinning process. The structure and properties of RBC nascent fiber were characterized by Fourier transform infrared spectrometry （ FTIR）, wide-angle X-ray dif- fraction （WAXD）, thermogrametric analysis （TGA）, scanning electron microscopy （SEM）, single fiber tensile strength test. The results showed that BC can be completely dissolved in the solvent system after lO-h high-speed stirring, which is dominantly a physical process without yielding any derivatives; the crystal form of RBC nascent fiber was transformed from cellulose crystal Ⅰ to Ⅱ , the crystallinity significantly decreased, the breaking strength was increased within the range of 0.54 - 1.36 cN/dtex while decreasing coagulation bath temperature, and the addition of anhydrous alcohol in coagulation bath was helpful to improving the fiber strength; the thermal stability of RBC nascent fiber slightly dropped as compared with that of BC; and RBC nascent fiber had rough surface with vertical and horizontal grooves, thin sheath and compacted core containing a small quantity of microholes.